Low-carb diets have been controversial for decades.
Some people assert that these diets raise cholesterol and cause heart disease due to their high fat content.
However, in most scientific studies, low-carb diets prove their worth as healthy and beneficial.
A low-carb diet not only causes more weight loss but also leads to major improvements in most risk factors for heart disease — including cholesterol.
Here are 10 proven health benefits of low-carb and ketogenic diets.
Hunger tends to be the worst side effect of dieting.
It is one of the main reasons why many people feel miserable and eventually give up.
However, low-carb eating leads to an automatic reduction in appetite ().
Studies consistently show that when people cut carbs and eat more protein and fat, they end up eating far fewer calories ().
Summary Studies indicate that cutting carbs can automatically reduce your appetite and calorie intake.
Cutting carbs is one of the simplest and most effective ways to lose weight.
Studies illustrate that people on low-carb diets lose more weight, faster, than those on low-fat diets — even when the latter are actively restricting calories.
One study in obese adults found a low-carb diet particularly effective for up to six months, compared to a conventional weight loss diet. After that, the difference in weight loss between diets was insignificant ().
In a year-long study in 609 overweight adults on low-fat or low-carb diets, both groups lost similar amounts of weight ().
Summary Almost without exception, low-carb diets lead to more short-term weight loss than low-fat diets. However, low-carb diets seem to lose their advantage in the long term.
Not all fat in your body is the same.
Where fat is stored determines how it affects your health and risk of disease.
The two main types are subcutaneous fat, which is under your skin, and visceral fat, which accumulates in your abdominal cavity and is typical for most overweight men.
Low-carb diets are very effective at reducing this harmful abdominal fat. In fact, a greater proportion of the fat people lose on low-carb diets seems to come from the abdominal cavity ().
Over time, this should lead to a drastically reduced risk of heart disease and type 2 diabetes.
Summary A large percentage of the fat lost on low-carb diets tends to be harmful abdominal fat that is known to cause serious metabolic problems.
Triglycerides are fat molecules that circulate in your bloodstream.
It is well known that high fasting triglycerides — levels in the blood after an overnight fast — are a strong heart disease risk factor (10).
One of the main drivers of elevated triglycerides in sedentary people is carb consumption — especially the simple sugar fructose (, , ).
On the other hand, low-fat diets often cause triglycerides to increase (16, ).
Summary Low-carb diets are very effective at lowering blood triglycerides, which are fat molecules that increase your risk of heart disease.
High-density lipoprotein (HDL) is often called the “good” cholesterol.
One of the best ways to increase “good” HDL levels is to eat fat — and low-carb diets include a lot of fat (, , ).
Therefore, it is unsurprising that HDL levels increase dramatically on healthy, low-carb diets, while they tend to increase only moderately or even decline on low-fat diets (, ).
Summary Low-carb diets tend to be high in fat, which leads to an impressive increase in blood levels of “good” HDL cholesterol.
Some people with diabetes who begin a low-carb diet may need to reduce their insulin dosage by 50% almost immediately (33).
In one study in people with type 2 diabetes, 95% had reduced or eliminated their glucose-lowering medication within six months ().
If you take blood sugar medication, talk to your doctor before making changes to your carb intake, as your dosage may need to be adjusted to prevent hypoglycemia.
Summary The best way to lower blood sugar and insulin levels is to reduce carb consumption, which may treat and possibly even reverse type 2 diabetes.
Elevated blood pressure, or hypertension, is a significant risk factor for many diseases, including heart disease, stroke and kidney failure.
Low-carb diets are an effective way to lower blood pressure, which should reduce your risk of these diseases and help you live longer (, ).
Summary Cutting carbs leads to a significant reduction in blood pressure, which should reduce your risk of many common diseases.
Metabolic syndrome is a condition highly associated with your risk of diabetes and heart disease.
In fact, metabolic syndrome is a collection of symptoms, which include:
- Abdominal obesity
- Elevated blood pressure
- Elevated fasting blood sugar levels
- High triglycerides
- Low “good” HDL cholesterol levels
However, a low-carb diet is incredibly effective in treating all five of these symptoms (36, ).
Under such a diet, these conditions are nearly eliminated.
Summary Healthy low-carb diets effectively reverse all five key symptoms of metabolic syndrome, a serious condition which increases your risk of heart disease and type 2 diabetes.
It turns out that low-carb diets increase the size of “bad” LDL particles while reducing the number of total LDL particles in your bloodstream ().
As such, lowering your carb intake can boost your heart health.
Summary When you eat a low-carb diet, the size of your “bad” LDL particles increases, which reduces their harmful effects. Cutting carbs may also reduce the number of total LDL particles in your bloodstream.
Your brain needs glucose, as some parts of it can only burn this type of sugar. That's why your liver produces glucose from protein if you don't eat any carbs.
Yet, a large part of your brain can also burn ketones, which are formed during starvation or when carb intake is very low.
This is the mechanism behind the ketogenic diet, which has been used for decades to treat epilepsy in children who don't respond to drug treatment (44).
In many cases, this diet can cure children of epilepsy. In one study, over half of the children on a ketogenic diet experienced a greater than 50% reduction in their number of seizures, while 16% became seizure-free (45).
Very low-carb and ketogenic diets are now being studied for other brain conditions as well, including Alzheimer's and Parkinson's disease ().
Summary Low-carb and keto diets have proven beneficial in treating epilepsy in children and are being studied for their effects on other brain conditions.
Few things are as well established in nutrition science as the immense health benefits of low-carb and ketogenic diets.
Not only can these diets improve your cholesterol, blood pressure and blood sugar, but they also reduce your appetite, boost weight loss and lower your triglycerides.
If you’re curious to boost your health, one of these diets could be worth considering.